1. Field of the Invention
The present invention is directed to a self contained means of pressurizing a fluid reservoir with air, creating a pressure differential between the contained fluid and the ambient atmosphere that propels fluid from, for example, a water ejecting toy gun or a dispensing container in either a continuous stream or in a selective manner.
2. Discussion of the Prior Art
Water guns have for decades been a very popular child's toy. Since the toy industry is very competitive, hundreds of different style water guns have been developed in an attempt to profit from the toy's inherent popularity. The most traditional forms of water guns are activated by a manual pumping action through the trigger. While such pump action water guns work, they are limited in the distance the water traveled, the amount of water projected and the duration of the pumping cycle. In an attempt to improve upon water guns, the toy industry has developed pressure activated water guns. Such pressure activated water guns work upon the principle of pressure differentials between the water held within the toy and the atmosphere. The water within the toy is subjected to a pressure higher than that of the ambient air. As a result, when the water within the toy is given an avenue of escape, the water will stream out under pressure.
Two primary types of pressure activated water toys exist. The first type is when the water itself is worked to a pressure higher than that of the ambient air. This type of water gun is exemplified by the following: U.S. Pat. No. 3,197,070 to Curtis F. Pearl et al, shows a water gun activated by trapping water in a collapsible area. As the device is collapsed, the pressure of the water builds, spraying the water out of the one small orifice left within the pressured area. Once the confined area is fully collapsed, the reexpansion of the area draws forth more water from a reservoir, thus priming the water gun for another cycle. U.S. Pat. No. 4,854,480 to Robert S. Shindo and U.S. Pat. No. 4,735,239 to Michael E. Salmon et al, both show toy water devices that use an elastic bladder to pressurize water. The bladders are filled with high pressure water, and the bladders respond by elastically deforming. The source of pressurized water is then removed and the water within the expanded bladder is held in place by a clamping device activated by a trigger. The water gun is used by selectively releasing the clamp, allowing the water to flow from the expanded bladder.
The second type of pressure activated water toys are toys that use air pressure to force water through squirt channels. Such toys that use this technology are exemplified by U.S. Pat. No. 4,214,674 to Jones et al. The Jones patent shows a two piece apparatus consisting of a pressurized water reservoir and a discharging gun. The Jones patent has a hand operated air pump. By way of additional example, U.S. Pat. No. 4,239,129 to Gary F. Esposito describes a water pistol and/or flashlight structure which includes a reciprocal pump within a liquid chamber or tank located itself within the gun housing. Like the pump employed by Jones et al, the pump of Esposito is a hand operated structure used to pressurize air within the tank after water has been added, and a trigger is used for subsequent release of the water. Battery operated lights and sound are also provided.
A primary disadvantage of the water guns employing a hand operated actuator to achieve pressurization is just that, they require the child to suspend play, spend a substantial amount of time operating the actuator, and then resuming play. It would therefore be highly desirable to provide a water gun in which the act of pressurizing the water tank closely does not require suspension of play or but actually becomes an exciting and enjoyable aspect of play.
In other fluid dispensing fields, there are even more compelling reasons for the availability of a simple, yet efficient manually operable pressurizing actuator. Specifically the use of chlorofluorocarbons (CFCs) and other flammable and or chemical pressurizing agents, though known to be harmful to the environment, are still in wide spread use.